Lactones and lactides, which are cyclic esters generally prepared by the condensation reaction of hydroxy acids or their derivatives, and polymerization products thereof, have been widely studied for numerous medical uses. For example, polymers derived from L-(-)-lactide, .alpha.-caprolactone, glycolide and p-dioxanone have been shown to have a wide variety of uses, including the preparation of various surgical devices such as sutures, suture coatings, surgical prostheses and implants, and as a carrier or matrix for sustained release of drugs. Many of these polymer compositions are advantageous for such medical uses because they are bioabsorbable and elicit minimal tissue reaction in animals.
In view of the demonstrated viability of using polymers derived from lactones and lactides for a variety of medical applications, there is a constant striving to develop new polymers and copolymers derived from such monomeric compounds. Accordingly, the development of these polymer systems is most desirable to advance the current state of the medical art.